The present invention relates to vehicle intrusion alarms and, more particularly, to an improved vehicle alarm which is easily armed and difficult to foil.
Prior art vehicle intrusion alarms have been characterized by arming sequences which involve multiple steps which are often not properly followed by vehicle operators. Even when the sequence is properly followed, the operator is never quite sure that the alarm system is armed and can only find out by entering the vehicle and tripping the alarm; of course, he must thereafter re-arm the system and once again be unsure that it is armed. Moreover, where attempts have been made to simplify the arming procedure, the resulting alarm system is generally easily foiled by an intruder.
It is an object of the present invention to provide a vehicle alarm system which is easily armed, difficult to foil, and which provides an indication to the operator when it is armed.
It is conventional in vehicle intrusion alarm systems to provide a delay between the time an intrusion is sensed and the sounding of an alarm. This delay, normally on the order of sixty seconds or so, permits the operator of the vehicle to enter the vehicle and disarm the alarm system without setting off the alarm. An intruder can easily enter the vehicle, steal contents therefrom, and be gone within this delay period.
It is therefore another object of the present invention to provide a vehicle intrusion alarm system in which there is no delay between most sensed intrusions and alarm actuation and yet which permits the vehicle operator sufficient time to enter the vehicle and disarm the alarm.
In prior art vehicle intrusion alarm systems a severe problem arises once the alarm is actuated in that the alarm continues to sound until it is disarmed by the operator. The result is annoying noise pollution and needless drain on the vehicle battery, for it is only necessary, for alarm purposes, to sound the alarm for a few minutes.
It is a further object of the present invention to provide a vehicle intrusion alarm system in which the alarm is automatically terminated a pre-determined time after actuation.